code: def testZero(self):
      # Define input vector, i.e. the autocorrelation vector
      zeroInput = zeros(1024)
      enhancedHarmonics = PercivalEnhanceHarmonics()(zeroInput)
      self.assertEqualVector(enhancedHarmonics, zeroInput)
  
file_path: essentia/test/src/unittests/rhythm/test_percivalenhanceharmonics.py
imports: from numpy import *
  from essentia_test import *
  from essentia.standard import MonoLoader, PercivalEnhanceHarmonics
  from math import sin, pi
label_desc: Use image node_id 3 for calling the TestPercivalEnhanceHarmonics obj's underlying member method code with example usage: obj.testZero() without return types